The invention relates to a transistor arrangement, an arrangement for the rectification and/or inversion of at least one electrical voltage, and an apparatus for the rectification and/or inversion of at least one electrical voltage. The invention additionally discloses a use for a transistor arrangement or an arrangement according, a use for an apparatus, and also a method for controlling a transistor.
At the present time, rectifiers and inverters, within a wide power range, are in many cases constructed from voltage-controlled transistors that can be switched on and off. In this case, in particular for the conversion of a DC voltage into a three-phase AC voltage, or vice versa, a six-pulse bridge circuit is known wherein a DC voltage source can be connected to a three-phase voltage source via inductor/inductances. In this case, the field effect transistors (FET) in particular MOSFETS, are often used for voltages of less than 100 V. In this case, source terminal and the drain terminal of the individual transistors are connected to a diode (in the case of a MOSFET, said diode is already fundamentally contained in the transistor), the diodes then performing the rectification of the three AC currents in a simple manner without further control. For the inversion of the DC voltage, that is to say the converse case, a specific driving of the transistors is required in order to switch the latter on and off according to a known method (for example using fundamental clocking or pulse width modulation). It was recognized in this case that this drive circuit required for inverter operation can advantageously be used to relieve the load on the diodes during rectifier operation by switching on the transistors connected in parallel. Such a method is known inter alia by the term “synchronous rectification” and reduces the voltage loss during rectification. What is disadvantageous in this case, however, is that there is additional need for control to determine the switching-on and switching-off instants of the diodes and of the MOSFETs, in particular taking account of the necessary protection times. This outlay can be obviated when using a self-controlled transistor such as is known from the publications “Neuartige Gleichrichterprinzipien zur effizienten Speisung von Kfz-Bordnetzen aus Klauenpolgeneratoren” [“Novel rectifier principles for efficient supply of motor vehicle electrical systems from claw pole generators”] (U. Amann; Dissertation at the Institute for Power Electronics and Control Engineering at the University of Stuttgart, 2002) and “A Smart Synchronous Rectifier for 12 V Automobile Alternators” (S. Rees, U. Ammann; Proceedings of the 34th IEEE PESC Conference 2003, page 1516 et seq.; Acapulco, Mexico), although at the same time dispensing with the possibility of inverter operation. Therefore, there is still the desire for a simplified effective rectifier and inverter.